


the worst thing

by wishingonalightningbolt



Category: Teen Wolf (TV)
Genre: Alternate Universe - High School, Alternate Universe - Human, Bottom Stiles Stilinski, Derek Hale & Scott McCall are Siblings, M/M, Plot What Plot/Porn Without Plot
Language: English
Status: Completed
Published: 2018-04-13
Updated: 2018-04-13
Packaged: 2019-04-22 10:14:15
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 3,714
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14306511
Author URL: https://archiveofourown.org/users/wishingonalightningbolt/pseuds/wishingonalightningbolt
Summary: Derek pulls a hand down his face, sighing. “I’m not gonna do anything about it, obviously. He just has a thing for me and it’s getting to my head, but he’s Scott’s best friend--”“Scott would literally kill you if you fucked Stiles.”His heart skips a beat. He curses it. “I’m not going to fuck Stiles,” Derek swears. “That would be a monumental mistake.”





	the worst thing

**Author's Note:**

> Hiya, welcome to this nonsense. I'm procrastinating my senior thesis and so I wrote this in about two hours and am just posting it no regrets.
> 
> The underage is because Stiles is sixteen and Derek is eighteen, and age of consent in CA is eighteen. Both characters are horny as fuck and down to pound.

Derek isn’t blind, nor is he a moron. He’s about to graduate from high school and he’s never been told he needs glasses, so he knows he isn’t imagining this. He knows he isn’t reading too much into it. He knows Stiles Stilinski is flirting with him.

Derek has never once looked at Stiles like a potential romantic or sexual partner. He’s known the kid since he was five years old, and granted Derek was only seven at the time, but the point stands. Stiles is like another brother to him. He’s Derek’s  _ actual _ brother’s best friend anyway, so it’s like Stiles and Scott are the same person. That would be weird, to want Stiles like that. That would be wrong.

It starts after Stiles’ sixteenth birthday. They celebrate at his house, and Derek comes along because he’s in a charitable mood and he likes talking to Stiles’ dad. Late in the evening, Stiles comes over to talk to him and places a hand on his hip, just for a second, and he smiles in a way Derek’s never seen him smile before, and he looks--

He looks like 140 pounds of twink, blotchy red cheeks, perfect fucking mouth, and an ass that Derek mostly pretends not to pay attention to. Derek’s nearly eighteen, so thinking about someone Scott’s age--someone Scott is  _ best friends  _ with--like that is weird. It’s not okay. And Derek doesn’t even like him like that anyway.

  
  


Stiles is unfortunately good at this. He’s hitting all the right nerves, showing up at the auto shop where Derek works after school, appearing around lockers and behind corners, even running into him in the school parking lot, right around where both of their cars seem to be parked. He’s relentless, and Derek has to admit that he’s paying a lot more attention that he used to. Stiles shows up fresh from a run one afternoon at the house (ostensibly to see Scott), dripping with sweat and peeling his shirt off. Derek pretends not to notice. Then he leans against Derek’s Camaro after class one day and makes a joke about overcompensation with sports cars, looking pointedly at Derek’s crotch.

Derek wants to smother him. And kiss him.

  
  


Stiles shows up to celebrate Derek’s eighteenth birthday. He’s perfectly normal most of the night, friendly and engaging, goofing off with Scott--but towards the end of the evening, when Scott is off somewhere else and Derek is heading through the hallway towards the kitchen, Stiles finds him.

Neither of them say anything, standing there in the dim light, staring at each other. He  _ can’t _ . He  _ won’t _ .

His mom appears at the end of the hallway, waving them over. “C’mon, boys. I need your help with this stuff.”

Derek shoves past him immediately, not bothering to think twice. He escaped this time, but he knows it was close. He knows that if his mom hadn’t interrupted when she did, he would’ve kissed Stiles. He would’ve  _ kissed Stiles _ .

  
  


The only person Derek can talk to about this is Boyd. Boyd is a fortress. He won’t say anything to anyone else, and he won’t make a big deal out of it. He’ll get it.

“Dude.”

Derek winces. “Yeah.”

“ _ Dude _ .”

“ _ Yeah _ , I know.”

Boyd raises both eyebrows, the international expression for  _ Oh, yeah? _

Derek pulls a hand down his face, sighing. “I’m not gonna do anything about it, obviously. He just has a thing for me and it’s getting to my head, but he’s Scott’s best friend--”

“Scott would literally kill you if you fucked Stiles.”

His heart skips a beat. He curses it. “I’m  _ not _ going to fuck Stiles,” Derek swears. “That would be a monumental mistake.”

  
  


The kissing should be weird. It’s not.

Kissing Stiles should feel  _ really fucking weird _ , but instead, it just feels good. He’s a good kisser, and he tastes a little bit like coffee, which makes Derek wonder what  _ he _ tastes like--

“Are you okay?” Stiles asks, leaning back, hands on Derek’s biceps.

Derek blinks. “I shouldn’t be here.”

Stiles looks around. They’re in the middle of the parking lot between the Dunkin Donuts and the Starbucks. There are a handful of other cars, but the mini mall is mostly abandoned, so it’s not as if anyone is around to see them.

Derek clears his throat, takes a step back. “I’m sorry, I shouldn’t have--”

Stiles doesn’t give him a chance to finish as he fists his hands in Derek’s shirt and pulls him back in, kissing him deeply once more. Derek, weak and pathetic, doesn’t even bother fighting it, kissing back eagerly, threading the fingers of one hand into Stiles’ hair.

They stay like that for a few long minutes before Stiles pulls back again, smiling this time.

“Jesus,” Derek breathes.

“My dad works late shifts on Sunday nights,” Stiles tells him. “He doesn’t get home until six in the morning.”

Derek licks his lips. “Stiles.”

“I won’t tell Scott.”

“No kidding. That’s not--there wouldn’t be anything to tell him if we just--didn’t do this.” Even as he says it, he feels himself being drawn into Stiles’ orbit, eyes caught on his mouth. “This is a bad idea. You’re only  _ sixteen _ .”

“You’re barely eighteen.”

“Still eighteen. Still an adult. Still too old for you.”

“Are you telling me or yourself?”

Fuck Stiles and fuck his perceptiveness. Derek frowns, crosses his arms over his chest to try to put more distance between them. “We can’t do this, Stiles. I don’t  _ want _ to do this.”

Stiles laughs, bright and loud, like it’s a fucking joke.

“Fuck you,” Derek spits.

“You can,” Stiles says. “I’m offering.”

  
  


Derek had sex with Paige after junior prom. They were bad at it for a while, but then they were better, and then they were actually good. After she dumped him for Tyler Wong, he hasn’t really had any interest in dating anyone else, let alone having sex. He’s not completely inexperienced with men--he and Danny almost hooked up at a party once, made out for a while and grinded--but he certainly hasn’t fingered someone’s asshole or sucked a dick. He’s at a loss, and yet, he can’t get the idea of trying all that stuff with Stiles out of his head.

It doesn’t help that the kid won’t fucking leave him alone.

**> Thinking about you**

It’s late, almost midnight, and Derek sees through the text immediately. He won’t respond to it.

**> Kissing you is so addictive**

**> I wonder what else you’re good at**

Derek turns off his ringer, turns his phone screen down so he can’t see it light up. He spends the next five minutes convincing himself not to look, and the five minutes after that jerking off, unable to stop himself.

  
  


The bathroom in the boys’ locker room has a lock on the main door, for reasons that escape Derek’s comprehension. All the same, when he and Stiles stumble through it, he’s grateful to have a lock, something he can throw to secure a barrier between them and the outside world.

“Damn it,” Derek mumbles into Stiles’ mouth, lifting him by the underside of his thighs, hoisting his knees up and around Derek’s hips.

Stiles only moans, tugging gently on Derek’s hair, rolling his hips.

“Jesus  _ fuck _ ,” Derek sighs, rolling his hips right back. “How are you doing this to me?”

There’s not really any conversation worth having right now, so Derek lets it go in favor of focusing on Stiles’ hands trailing down his neck, over his shoulders and arms. He focuses on Stiles’ hips, sliding against his own, and on Stiles’ thighs, gripping him around the waist. He loses himself in Stiles’ mouth, kissing him until there’s nothing going on between his ears but a bunch of white noise.

“Wait, wait, wait,” Stiles pants some time later, hands working between them as he unbuttons his jeans, unzips himself.

Derek’s too busy staring at his cock to protest.

“You too,” Stiles says, pulling himself off quickly. “If we come in our jeans it’ll be worse, I promise.”

A broken noise fills the space, and Derek realizes that it came from  _ him _ . “Fuck,” he sighs. “Stiles, I--”

“I know you want to,” Stiles says. “It’s okay, Der. I want you to. I want to see you. I want to see you come.”

Derek’s never felt so broken in his life, so helpless, so completely enslaved to the whim of another person. And the worst part is, he loves it. It makes him feel free. It makes him feel  _ good _ . 

It makes him a horrible person.

  
  


He can’t look Scott in the eye anymore. He has to settle for an eyebrow, or his nose, heart pounding in his chest no matter what. He’s horrified, full of guilt, and still, deep down, overwhelmingly pleased with himself.

When Stiles is around the house, camped out on the couch playing video games with Scott or just over for dinner, Derek can’t look at him either. He can hardly even talk. He’s pathetic.

  
  


Stiles sucks his dick in the back of his Jeep, parked way out in the preserve, hidden under a canopy of trees. Derek gets to pull his hair and make as much noise as he wants, and he gets to come down Stiles’ throat and then kiss him as deep and messy as he likes.

“I’ve never,” Derek admits, holding the base of Stiles’ cock. He’s tucked between Stiles’ thighs, positioned strangely in the backseat, but he doesn’t have any intention of stopping right now.

“Take your time,” Stiles says. “I’m not in a hurry.”

He does. He takes his sweet time, learning how it feels, what’s good, what’s  _ better _ , what he should do when he wants Stiles to shake and whimper. Stiles barely makes a noise the whole time, hand tender on the back of Derek’s neck, but Derek doesn’t mind, isn’t too obsessed with what Stiles is doing. Right now, he cares more about the way his cock is hardening between his legs as the weight of Stiles’ cock inside his throat makes him gag.

Later, Stiles jerks him off and whispers filthy things in his ear, things that Derek can barely picture, let alone actually imagine doing. Still, it somehow fucking works, and he comes desperately, clinging to Stiles for life.

  
  


Stiles gropes him when he bends over to get something out of the bottom drawer of the fridge.

“Fuck,” he spits, shoving Stiles’ hand away. “Don’t do that.”

“Sorry,” Stiles says, but he doesn’t seem to mean it. “I texted you yesterday. You never responded.”

Derek swallows. “Yeah. Sorry.”

“So, do you want to come over tomorrow?” Stiles cocks his head, smiles that terrible fucking smile. “Think you could come up with an excuse for Melissa?”

“It’s not a good idea, Stiles,” Derek tells him.

“It’s better than most of our other ideas lately,” Stiles argues. “A real bed, with real privacy, instead of getting off in bathrooms and cars.”

Derek clenches his jaw, tries not to think about those bathrooms and cars in any specifics. “This--you and me--whatever we’re doing. It’s not a good idea. We have to stop.”

Stiles sighs. “Derek, you say that every time.  _ It’s not a good idea; what if Scott finds out; your dad will kill me _ . You’ve gone through every excuse on the planet, and you’re still here.”

“I live here.”

“Come over tomorrow,” Stiles says. “I haven’t even seen you naked yet.”

  
  


It’s fucking electric. For as much as Derek protests, being with Stiles is--unbelievable. They can’t keep their hands off each other, and within twenty minutes of Derek showing up, Stiles is fingering himself, knees spread on the bed with his forehead against the pillow. Derek is behind him, watching, mouth open, cock in his hand, with what is probably a really dumb expression on his face. 

“How did you learn how to do this?” Derek asks when he’s on his back and Stiles is on top of him, guiding Derek’s cock inside of himself.

Stiles laughs softly. “The Internet. Trial and error. I’m a very creative masturbator.”

Derek grips Stiles’ hips tightly. “Prove it. Fucking--move. Ride me. Do something.”

“I thought you’d never ask.”

It’s different with him. Stiles is fearless and sexy and he knows what he wants. He’s exactly the wrong kind of person for Derek to get mixed up with--especially when he’s sixteen fucking years old--but he can’t help it. Stiles is addictive. Stiles is--better than anything else Derek’s known.

He rides Derek’s cock slowly at first, letting himself get used to the sensation, but soon he’s speeding up, fucking himself faster, head thrown back as he rises and falls on Derek over and over and over. And Derek is just going along for the ride, holding on tight. He can’t do anything but try to meet Stiles’ hips with his own and hope that he’s making it good, making it something Stiles wants. If the noises coming out of his mouth are any indication, Stiles doesn’t have any complaints.

When he comes, he cries out-- _ loudly _ . His head is tipped back to the ceiling, hand on his cock, and he squirms on Derek, clenches around him and comes. It’s so much,  _ too much _ , and Derek comes just as easily, digging his fingers into Stiles’ thighs.

  
  


“Fuck me like this,” Stiles whispers in the dark, hands on Derek’s shoulders. Derek’s on top now, settled between Stiles’ legs, just kissing him sweetly, slowly. They’ve been perfectly lazing together, neither of them willing to break the spell, but Derek is hard again--as he always seems to be around Stiles--and he wants.

“It’s okay,” Stiles reassures him. “Whatever you want. Fast or slow--I don’t care. Just fuck me, Derek.”

He breathes against Stiles’ collarbone as he pushes inside once more. His cock is oversensitive but he can’t stop himself all the same. They’re quiet, moving together, and Derek can take what he wants now, has all the power to fuck himself hard and fast into Stiles’ open body. But that’s not what he wants, not once he’s established a smooth, tender pace that makes his spine light up and his balls ache.

Stiles seems like he’s into it too, a small smile curling on his mouth, hands moving gently across Derek’s shoulders, down his arms. “You feel amazing,” Stiles sighs, and Derek’s stomach twists. “You feel so good inside of me, Derek.”

Derek closes his eyes tight, focuses on the rhythm of his hips.

“Ah,  _ fuck _ , Derek.”

Just Stiles saying his name is making him feel all sorts of ways.

“You’re so--you’re so fucking big inside of me, Der.”

“Fuck,” Derek sighs. “Don’t--don’t say shit like that.”

“Why not? It’s true.”

“I’m gonna come too fast.”

Stiles laughs, petting his hands through Derek’s hair. “That’s okay--that’s good. I want to feel it. I kind of missed it last time.”

“Jesus Christ, Stiles.”

“C’mon, Der. Come in me.”

 

Boyd blinks.

Derek feels like digging himself a grave.

“What are you gonna tell Scott?”

“ _ Nothing _ ,” Derek hisses. “I’m not gonna tell him anything.”

“What if Stiles tells him?”

“He won’t. He’s just as worried about Scott’s reaction as I am.”

Boyd cocks his head. “Stiles’ dad is a cop.”

“Trust me, I’m completely aware.”

“He’ll fucking shoot you, dude.”

Derek sighs. “Yeah. Yeah, I know.”

  
  


Derek gets accepted to Berkeley with a great scholarship. The first person he wants to tell is Stiles.

  
  


He’s having a really, really good dream. His entire body feels fucking amazing, totally relaxed, totally at the whim of the mouth around his cock. It’s--it’s so fucking good--

“Fuck,” Derek spits, jerking backwards. His cock falls out of Stiles mouth, who looks up at him with a half-pleased, half-surprised expression.

“Hey,” Stiles says. “Scott’s asleep.”

Derek sits up, rubbing his eyes. “Don’t. He’s right next door.”

“He sleeps through thunderstorms.”

“Yeah, well, my mom doesn’t and she’s just down the hall.”

Stiles licks his lower lip. It’s ridiculously attractive.

“Congrats on Berkeley,” Stiles says.

“Oh. Yeah. Thanks.”

“You won’t be too far away. Probably still visit pretty often, right?”

Derek swallows tightly. “Yeah. Probably.”

Stiles smiles. “Derek, it’s okay. There’s no pressure here. I get it.”

“Get what?”

“I get it if you don’t want something more from me. If this is just sex, I get it.”

Derek never even thought about, couldn’t even conceive of a world in which it was more than sex, in which Stiles was his boyfriend or--or--

“It’s not,” Derek says, unthinking. “It’s not just sex.”

Stiles’ face softens. “Yeah?”

His mind is racing, but he can’t help but say what he’s thinking. “I’m terrified. I have no idea what I’m doing. I don’t--I like you. And I know that I shouldn’t. And I know it’s terrible timing.”

“So what?” Stiles responds in perfect Stilinski fashion. “So we’ll figure it out together. So I’ll drive to see you on weekends and let you fuck me in your tiny freshman dorm room.” He leans over Derek’s body, closing the distance between them, and kisses Derek sweetly. Derek can taste himself on Stiles’ tongue. “You can be my boyfriend.”

Derek’s heart constricts. “What about Scott?”

“He’ll get over it. He wants me to be happy. He wants you to be happy.”

“He’ll kill me. Your dad will kill me. My  _ mom _ will kill me.”

“You’re not doing anything wrong.”

“You’re  _ sixteen _ .”

Stiles laughs, kisses him again. “You’ve already had your dick in my ass, Derek. I think we’re past the age argument, don’t you? I bet everyone will be way more chill about this than you think. With the possible exception of my father. You did devirginize his only son.”

“Jesus.”

“In your defense, I am very seductive.”

“No kidding.” Derek kisses him again, tired of talking. If they’re doing this anyway, he might as well get something out of it.

  
  


They throw a party for Derek, to celebrate Berkeley. At some point during the festivities, Stiles takes ahold of his hand and doesn’t let go. Derek doesn’t argue.

“We’re dating now,” Stiles says frankly to Scott, who pulls a face like he just saw his grandmother naked. “We make each other happy and if you’re gonna be an asshole about this, you’re gonna hurt us both.”

Scott frowns. “I’m not gonna be an asshole. I just think you could do better.”

“Ouch,” Derek says.

“Derek’s good enough for me,” Stiles decides. “I earned him fair and square.”

“I don’t like the idea of you getting it on with my brother.”

“Sucks,” Stiles says frankly. “Now step aside. We have to drop the bomb on my dad.”

  
  


Sheriff Stilinski does not threaten to shoot him, but he does completely change the way he looks at Derek now. His gaze is steady, careful, like he’s still trying to decide whether or not he approves, and Derek isn’t going to give him a reason not to. That’s hard, though, because Stiles is...Stiles.

“We can’t,” Derek sighs, squirming against the seat. “You have a curfew and if you’re late he won’t let you go to prom.”

“He’s not gonna stop me from going to prom. You’re about to graduate. He gets how important it is.”

“Stiles, seriously.”

“You’re not trying very hard to stop me,” Stiles points out, pulling his slick fingers from himself and wrapping them around Derek’s cock. Derek hisses, head falling back against the leather seat of the Camaro. “Tell me you don’t want to fuck me, Der. Say it.”

“Fuck you.”

“How sweet of you to ask.”

Later, when he drops Stiles off, it’s twenty minutes past his curfew and his clothes are mussed, his hair a tangled nest. It’s no secret what they were off doing, and Derek feels like he’s going to burst into flames.

“I’m gonna get murdered,” Derek tells him after he leans in for a goodbye kiss.

“Definitely not,” Stiles reassures him. “My dad actually kind of loves you. He thinks you’re a good influence.”

“Shit.”

Stiles laughs, kisses him again. “You are, Derek. You’re good for me. You’re good  _ to _ me.”

_ I love you _ , Derek thinks, and it scares him so, so bad. “I love you,” he says, and it scares him less.

“Oh,” Stiles breathes. “Yeah, I--I love you too, Derek. Of course I do. I love you.”

  
  


They go to prom with a big group of friends and crash in the living room of Scott and Derek’s house, all of them spread out across couches and floor. Scott and Kira get up at some point--long after Melissa’s gone to bed--to go into his room, and Stiles, who’s a little bit drunk, squeezes Derek’s arm.

They’re lying in a puddle in the middle of the room. Derek didn’t have anything to drink, but Stiles certainly did, so he ended up tackling Derek onto the floor, nuzzling into his throat. They stayed there for a nice long time while people drifted off around them, but now it’s clear Stiles has other plans.

Up in Derek’s room, in the dark, pressed against the closed door, Stiles holds Derek’s face in his hands and says, “You’re the best thing that’s ever happened to me.”

Derek can’t fight the urge to kiss him. When he finally pulls back, Stiles’ eyes are glassy, his mouth wet. His mind is racing and his chest feels tight. “You’re the worst thing that’s ever happened to me,” Derek tells him.

“Fuck you,” Stiles laughs.

“I mean it. I didn’t--I was fine until you showed up, distracting me, making me want you, making me fall in love with you.” Derek breathes against his jaw, kisses him there. “Now I’m ruined. Now I can’t stop thinking about you, wanting you, fucking needing you. I’m a mess.”

Stiles holds onto his jaw, brings him back to kiss. “Tell me you love me,” he demands.

“I love you,” Derek says easily. “I fucking love you.”

“Tell me I’m exactly what you need.”

“You’re all I ever need.”

Stiles kisses him once more, hot and fierce. “Tell me you regret it, falling for me.”

Derek’s throat constricts, his tongue caught.

“Say it, Derek. Tell me you regret it.”

“I can’t,” he admits.

“Yeah,” Stiles says. “I know.”


End file.
